1. Field of the Invention
This invention relates to a support cone being truncated to a frustum for use inside a toroidal heat exchanger. The support cone directs air flow through the heat exchanger and also presents a mounting location for a hydraulic fan driving motor which is responsive to engine cooling requirements.
2. Description of the Prior Art
The use of static toroidal or annular heat exchangers are being contemplated for a broad range of applications due to the inherent efficiency of this type of heat exchanger. Compared with the flat, slab, or plinth type heat exchanger constructions the static toroidal units have several capacity and efficiency advantages. For instance, when a rectangular plinth type radiator is used a circular fan cannot pull or push an even and consistent flow of air through the heat exchanger core. Generally, the air is presented to the heat exchanger on a relatively circular area thus the corners of the heat exchanger don't receive the amount of air flow that the central sections receive. Also the fan usually is destined to operate at a reduced efficiency level due to the lack of lateral space necessary to install an efficient flow improving fan shroud in a typical vehicle embodiment. Air flow through the toroidal or annular heat exchanger is propagated by the use of either a "pusher" or alternatively by a "sucker" type fan. As this fan is generally mounted at one annular opening of the toroidal heat exchanger the flow of air in respect to volume and velocity, through each stratum of the heat exchanger may vary. In other words, air flow through the radial passages of the heat exchanger at remote stratum areas could be less than air flow through the heat exchanger in the middle of the radial air passages.
In order to improve flow to areas at the remote, distant or extreme portions of the heat exchanger this invention presents an interior shroud or more properly a support cone truncated to a conical frustum to direct air in an efficient manner. This support cone in a basic embodiment is generally conical with the truncated reduced diameter portion in proximity to the mounted fan. The truncation plane acts as a mounting surface to accommodate a hydraulic motor mounted inside the support cone.
This invention contemplates the use of a variable speed hydraulic motor which is responsive to an engine coolant temperature sensing control system capable of allowing the fan driving hydraulic motor to be run at a speed related to the amount of engine cooling required.
A toroidal or static annular heat exchanger as contemplated for use with the proposed system is known in the prior art. The known devices, however, use conventional fan drive systems and are not provided with flow improving internal shrouds. Also shown in the prior art is a hydraulically driven fan driving means responsive to engine coolant temperature. This embodiment shows a flat radiator and only a rudimentary conventional shrouding. The main emphasis is focused more to the devices necessary to prevent hydraulic fluid being preferentially pumped to the fan motor when the fluid is more critically needed by other hydraulic systems.
One of the significant contributions of this invention over the prior art is the use of the support cone to improve the air flow to the heat exchanger core while at the same time providing a mounting location for a variable speed hydraulic motor to drive the fan.